PSYCHOLOGICAL TASK

Yale Center for British Art
Book of Urizen
Copy A, Plate 4
Courtesy of Wikipedia

Percival feels that Blake reenacted the reconciliation of his own disparate psychological divisions in his myth of division and reunion. Because he overcame a fractured psyche, he had insight to share on repairing the broken unity.  
 
Here is a quote from Page 96 of William Blake's Circle of Destiny  by Milton O Percival:
 
"Blake's private and personal experience had bred him to his task. The strife that he depicts in the myth of an historical and cosmic stage had often been enacted on the microscopic stage within himself. A born mystic, he was haunted by the demon of rationalism. A hater of systems, he could not rest without one of his own. He was now Los, the inspired Prophet, and now Urizen, the doubting Spectre. One set of voices said: 'Follow the gleam.' Another set urged: 'Paint like Rembrandt. Engrave like Bartolozzi. Win recognition at any cost.' Nor did his struggle end with artistic indecisions. There were other on less severe contentions between his inner principle, energetic and masculine, and his outer principle, passive and feminine. The delusive beauty of outward nature and the delusive pleasure of intellectual revery often threatened the integrity of his mind. Psychological dissociation was an ever present danger. Hence the reality, the comprehension, the marvelous fairness, in the depiction of the contending figures. The personages of his cosmic myth were familiar denizens of his own breast. His own triumphant struggle against disorganization within himself gave him the insight to depict a disorganized but finally triumphant world."

Milton, Plate 22 [24], (E 116)
"Tho driven away with the Seven Starry Ones into the Ulro
Yet the Divine Vision remains Every-where For-ever. Amen.
And Ololon lamented for Milton with a great lamentation.

While Los heard indistinct in fear, what time I bound my sandals
On; to walk forward thro' Eternity, Los descended to me:         
And Los behind me stood; a terrible flaming Sun: just close
Behind my back; I turned round in terror, and behold.
Los stood in that fierce glowing fire; & he also  stoop'd down
And bound my sandals on in Udan-Adan; trembling I stood
Exceedingly with fear & terror, standing in the Vale             
Of Lambeth: but he kissed me and wishd me health.
And I became One  Man  with  him  arising in my strength:
Twas too late now to recede. Los had enterd into my soul:
His terrors now posses'd me whole! I arose in fury & strength."